HBV serum transcriptome analysis

This project aimed to characterize the hepatitis B virus (HBV) serum transcriptome among different HBV genotypes and clinical phases by RNA long read sequencing (Nanopore). The study also included evaluation of 3 methods to identify HBV RNA isoforms and estimate the proportion of each within each serum sample.The study specifically aimed to detect and characterize (proportion, read length, etc.) the HBV transcriptome present in serum/plasma of clinical specimens. Although HBV is a DNA virus, it is understood that encapsidated HBV RNA species are secreted to the serum during viral replication; however, the specific HBV viral RNA load in serum/plasma is quite low (as detected by direct RNA sequencing or Nanopore PCR-cDNA sequencing), and as such the raw reads have very little HBV RNA (<0.1%). The majority of reads are comprised of human SIRV/ERCC control transcripts (approx. 40%), non-specific reads (bacteria, archaea, other - approx. 40%), or are unclassified (approx. 19%) as determined by KRAKEN2 analysis.